Core wrapping machine

ABSTRACT

A machine for wrapping fibrous reinforcing material around a core member of a somewhat fragile nature, such as foam plastic. Miltiple strands of reinforcing material are wrapped helically in opposite directions as the core member passes through the machine, the reinforcing being fed from stock cartons secured on simple supporting frames which are rotated about the core member. The frame units are circumferentially supported and have open center portions for passage of a variety of core members through adjustable guide means.

United States Patent n91 Shear, Jr.

[ 1 June 19, 1973 CORE WRAPPING MACHINE [76] Inventor: Herbert J. Shear, Jr., 626 Live Oak Drive, El Cajon, Calif. 92020 22 Filed: Feb. 10,1972

211 Appl. No.: 225,173

[52] US. Cl. 57/15 [51] Int. Cl. D02g 3/00 [58] Field of Search 57/1 R, 3, 6, l3,

[56] References Cited UNITED STATES PATENTS 1,857,820 5/1932 Rice... 57/16 2,111,630 3/1938 Johnson et a1.. 2,112,294 3/1938 Lilley 3,048,078 8/1962 Kaplan 3,129,631 4/1964 Hill et a1. 57/163 X Wasserman 357/16 Korschatzky et al. 57/15 Primary Examiner-Donald E. Watkins Att0rney-Carl R. Brown and Neil F. Martin [57] ABSTRACT A machine for wrapping fibrous reinforcing material around a core member of a somewhat fragile nature, such as foam plastic. Miltiple strands of reinforcing material are wrapped helically in opposite directions as the core member passes through the machine, the reinforcing being fed from stock cartons secured on simple supporting frames which are rotated about the core member. The frame units are circumferentially supported and have open center portions for passage of a variety of core members through adjustable guide means.

10 Claims, 4 Drawing Figures PATENIEBJUII ems SHEETZUZ Fig. 4

CORE WRAPPING MACHINE BACKGROUND OF THE INVENTION Numerous machines have been developed for wrapping various layers of material around a core, such as in the manufacture of insulated electrical cable. Usually the cable passes through a rotating head carrying tape or other wrapping material on spools. In a continuous operation this is satisfactory, but for wrapping short lengths of core the starting and stopping inertia of the machine and the rotation of the supply spools can cause undue strain on the core and over-running of the wrap. To obtain a tight wrap there is usually considerable tension on the wrap material, which is acceptable when wrapping a strong core, as in electrical cables. For wrapping various lengths of fragile core material, such as foam plastic, the conventional cable wrapping techniques and apparatus are not suitable.

SUMMARY OF THE INVENTION The apparatus described herein will wrap stranded material, such as glass fiber roving, around a core of foam plastic or the like, to produce reinforced light weight material. One particular use for such material is in the structure of a fiber reinforced plastic boat, in which the reinforced core material is laminated to the skin with resin to provide both structural rigidity and buoyancy.

The machine has a pair of frames which are rotated in opposite directions about a common axis, each frame having means for holding a plurality of stock cartons of fibrous wrap material. Core material is passed axially through the machine, by any suitable feed means, as the frames rotate and wrap the fibrous material helically around the core. The glass fiber roving intended for use on the machine is supplied in coiled form in a standard carton and is withdrawn through an opening in one side, without the need for rotating the carton or coil. Thus there is no starting and stopping inertia to consider in the feed of the wrap material, making it possible to operate the machine intermittently for various short lengths of core. Means is provided to apply a light tension on the wrap material, to obtain a close wrap without damaging the core.

The primary object of this invention is to provide a new and improved core wrapping machine.

Another object of this invention is to provide a new and improved core wrapping machine which will wrap multiple strands of material helically in opposite directions on a core.

Another object of this invention is to provide a new and improved core wrapping machine which will wrap various short lengths of low strength core material.

A further object of this invention is to provide a new and improved core wrapping machine which can utilize stock cartons of fibrous wrapping material, without the need for preparation or special dispensing means.

Other objects and many advantages of this invention will become more apparent upon a reading of the following detailed description together with an examination of the drawing, wherein likereference numerals refer to like parts throughout and in which:

FIG. 1 is an end view of the machine.

FIG. 2 is a sectional view taken on line 2-2 of FIG. 1.

FIG. 3 is a sectional view taken on line 3'3 of FIG. 2, with the structure rotated.

FIG. 4 is a perspective view of a portion of wrapped core material.

DESCRIPTION OF THE PREFERRED EMBODIMENT The machine comprises a pair of similar frame units 10 and 12, rotatably mounted on a base 14 in spaced coaxial relation. Each frame unit has a large diameter ring member 16 with an internal ring gear 18 and is supported peripherally, since thecentral portion must be open. Various bearing and roller means may be suitable, the supporting structure illustrated comprising upright pairs of posts 20 and 22 fixed on base 14, each post carrying a pair of freely rotatable support pinions 24 on which the ring gear 18 rides.

' Mounted on base 14 is a motor 26 having a gearbox 28, which drives a pair of drive pinions 30 and 32 in opposite directions. Drive pinion 30 engages the ring gear in frame unit 10 and drive pinion 32 engages the ring gear in frame unit 12.

Fixed to ring member 16 of frame unit 10 are chordally extending support members 34, held in a substantially square configuration by tie plates 36. Support plates 38 projecting inwardly from members 34 support a multi-sided open box frame 40 in axial position on the frame unit 10. Identical supporting structure on frame unit 12 holds a box frame 42 in axial position. The two frame units are mounted with their ring members in face to face relation and the box frames outside at opposite ends of the assembly. Each box frame is illustrated as a substantially cubical structure with a square inner frame, 44 fixed to support plates 38, and a square outer frame 46, the inner and outer frames being connected at their corners by bar members 48 extending parallel to the axis of the machine.

Box frame 40 is designed to hold a standard container or carton 50 on each of its four sides surrounding the axis, each carton being secured by a strap 52, or similar means, passed around bar members 48. The cartons contain stranded fibrous material in coiled form, so that a strand 54 can be withdrawn through an opening 56 in the inside wall of the respective carton. To apply a light tension to the wrap, each strand 54 is passed through a pair of eyes 58 fixed to the inside of inner frame 44, the eyes causing a frictional drag as the strand is fed out. Other frictional or tension applying means may be equally suitable.

Box frame 42 is similarly loaded with cartons 60 secured by straps 62, the strands 64 being extracted through openings 66 in the cartons. On box frame 42 the strands are threaded through friction applying eyes 68 on the outer frame 46, as in FIGS. 2 and 3.

A core member 70, to be wrapped, is passed through the machinesubstantially along the axis. For alignment a guide bar 72 is fixed between posts 22 and has a pair of upright pins 74 between which the core member slides. A retaining bar 76 is vertically slidable mounted on pins 74 and is secured by lock screws 78 to confine the core member with a suitable sliding clearance. The core member is moved by any suitable feed means, either manual or mechanical, at a convenient speed for applying the wrap.

As the frame units 10 and 12 are rotated by motor 26, the strands 54 are wrapped around the core member in one direction of rotation, and strands 64 are wrapped over strands 54 in the opposite direction of rotation. The helical pitch of the wrap will depend on the relative speed of core member advancement and the rotation of the frame units. The wrapped core is carried through guide rollers 80 mounted on a post 82, or other suitable guide and support means.

In the primary use of the machine, the core member 70 is of foam plastic as used for flotation filling in a boat hull formed from glass fiber reinforced plastic. The flotation material is bonded to the hull with resin and becomes part of the structure. By wrapping the foam material in lengths with glass fiber roving, the structural strength is greatly increased while buoyancy is retained. Many pieces of foam core material of varying lengths are needed to build up a layer in a boat hull, and the pieces can be fed through successively for wrapping and cut apart after leaving the machine. 8s illustrated in FIG. 4, adhesive tape 84 may be used to hold the cut ends of roving strands until the wrapped core material is resin bonded, either prior to or after placement in a structure.

By drawing the strands from non-rotating coils, there is no inertia problem in intermittent operation at low speed for which the machine is particularly suited. From one to four cartons of wrap material can be mounted on each frame unit, depending on the density of wrap required. If necessary, the frame units may be built to hold more than four cartons of wrap material, allowing a dense wrap to be made at a fast advance speed of the core without requiring a high rotational speed of the frame units. At the low speed of operation intended, balance is not a critical problem. With the large open center portions of the frame ,units, there is ample space for conveyor, roller, or other such support means as necessary for carrying the core material.

Having described my invention, I now claim.

1. A core wrapping machine, comprising:

a base;

a pair of frame units rotatably mounted on said base in spaced coaxial relation;

drive means for rotating said frame units in opposite directions;

each of said frame units having an open central portion for passage of a core member substantially axially therethrough;

and support means on each frame unit for holding a plurality of containers of coiled stranded wrap material, spaced around the axis of rotation.

2. A core wrapping machine according to claim 1, wherein said support means comprises a multi-sided open box frame extending axially and having means for holding a wrap container on each side thereof.

3. A core wrapping machine according to claim 1, and including guide means mounted between said frame units for guiding a core member substantially along the axis of rotation.

4. A core wrapping machine according to claim 3, wherein said guide means is adjustable to receive various sizes of core members.

5. A core wrapping machine according to claim 3, and including frictional tension applying means on each frame unit, through which the stranded wrap material is passed. I

6. A core wrapping machine according to claim 1, wherein each of said frame units includes a ring member having an internal ring gear therein;

said drive means comprising a motor mounted on said base and having oppositely driven pinions engaging said ring gears.

7. A core wrapping machine according to claim 6, wherein said support means comprises a multi-sided open box frame fixed centrally in each of said ring members, extending axially therefrom;

each box frame having means for securing a wrap container on each of its sides.

8. A core wrapping machine according to claim 7, wherein said frame units are mounted with the ring members in spaced face to face relation and said box frames extending outwardly on opposite sides.

9. A core wrapping machine according to claim 8, and including guide means mounted on said base between said frame units, with adjustable means for guiding a core member substantially axially through the machine. v

10. A core wrapping machine according to claim 9, and including frictional tension applying means through which the stranded wrap material is passed, said tension applying means being mounted on each box frame at the end toward the direction of advance of a core member. l III 

1. A core wrapping machine, comprising: a base; a pair of frame units rotatably mounted on said base in spaced coaxial relation; drive means for rotating said frame units in opposite directions; each of said frame units having an open central portion for passage of a core member substantially axially therethrough; and support means on each frame unit for holding a plurality of containers of coiled stranded wrap material, spaced around the axis of rotation.
 2. A core wrapping machine according to claim 1, wherein said support means comprises a multi-sided open box frame extending axially and having means for holding a wrap container on each side thereof.
 3. A core wrapping machine according to claim 1, and including guide means mounted between said frame units for guiding a core member substantially along the axis of rotation.
 4. A core wrapping machine according to claim 3, wherein said guide means is adjustable to receive various sizes of core members.
 5. A core wrapping machine according to claim 3, and including frictional tension applying means on each frame unit, through which the stranded wrap material is passed.
 6. A core wrapping machine according to claim 1, wherein each of said frame units includes a ring member having an internal ring gear therein; said drive means comprising a motor mounted on said base and having oppositely driven pinions engaging said ring gears.
 7. A core wrapping machine according to claim 6, wherein said support means comprises a multi-sided open box frame fixed centrally in each of said ring members, extending axially therefrom; each box frame having means for securing a wrap container on each of its sides.
 8. A core wrapping machine according to claim 7, wherein said frame units are mounted with the ring members in spaced face to face relation and said box frames extending outwardly on opposite sides.
 9. A core wrapping machine according to claim 8, and including guide means mounted on said base between said frame units, with adjustable means for guiding a core member substantially axially through the machine.
 10. A core wrapping machine according to claim 9, and including frictional tension applying means through which the stranded wrap material is passed, said tension applying means being mounted on each box frame at the end toward the direction of advance of a core member. 